The present invention relates to a heat-storing composition for a heat-storing means in air conditioning apparatus utilizing solar heat.
Air conditioning utilizing solar heat, etc. is carried out either by using water as a heat-storing material to utilize its sensible heat or by using a hydrated salt to utilize the latent heat of melting and solidification. An example of the hydrated salt is calcium chloride pentahydrate (melting point: 29.2.degree. C.) for a heat pump. When the heat of lukewarm water from boilers, the waste heat from plants, etc. are to be stored, without using a heat pump, to utilize the heat in heaters in the air conditioning apparatuses, a heat-storing material having a melting point in a temperature range of 40.degree.-50.degree. C. is required. To this end, sodium thiosulfate pentahydrate (Na.sub.2 S.sub.2 O.sub.3.5H.sub.2 O) is excellent owing to the melting point of 48.5.degree. C., heat-storing capacity as high as 82 cal/cc, and low cost, but it has such disadvantages as occasioning of much supercooling at the solidification. That is, supercooling by 20.degree.-30.degree. C. takes place in a glass vessel, failing to release the stored heat at the desired temperature.